| 摘要 |
<p>The device is for limiting the angle of vision to prevent illegal observation of pin numbers used with automatic teller machines. It comprises a grid of transparent tubelets of a specific length which limits the angle of vision. The grid is positioned in front of the information to be screened. The overall length of the grid is approximately 9 cm and the width is approximately 6 cm. The tubelets are rectangular and the ratio between their individual height and their width is determinant for the size of the angle of vision. As this ratio is greater than 4, an outstanding screening is achieved.</p> |
